Etymology

In Latin, incendio is the dative or ablative singular of incendium, "fire", and can mean "to fire" or "for fire" (dative), "by fire" or "with fire" (ablative of instrument or means). Thus, the incantation is a way of calling upon fire to burn a desired object, since the spell caster wills harm to be done to an object "by (means of) fire."

"Incendio" is the Catalan and Portuguese word for "fire". Also, in Italian the word "Incendio" refers to a great fire similar to that one made by Bellatrix to Hagrid's house.

"Incendio" (pronounced in-cen-DI-u) is also the first person singular of the present of the Spanish verb "incendiar", meaning "to set fire to".

In the video game adaptations of Philosopher's Stone and Chamber of Secrets, Incendio is the Bluebell flames charm Hermione uses in the first book. It is used primarily to wilt dank-loving, threatening plants and burn through spider webs. In the later games it resumes its use as a spell to conjure a small burst of normal fire.

When Rowle used the spell offensively against Hagrid's hut, it caused an explosion, rather than simply lighting it on fire.

Incendio is the first known spell to be cast in the series, although magical devices (Albus'sPut-Outer), abilities (Animagi) and beings (Hagrid) appeared before.

In the sixth film, Bellatrix uses this spell to set Hagrid's hut on fire instead of Rowle.